Sunderland have completed their third signing in 24 hours after sealing Craig Gardner's switch from Birmingham.
Skysports.com reported earlier on Thursday that Gardner was undergoing a medical on Wearside.
And the Black Cats have now confirmed that the 24-year-old midfielder has signed a three-year contract for an undisclosed fee.
However, it is believed Sunderland have agreed to pay in the region of £6million for Gardner, who joined Birmingham from local rivals Aston Villa 18 months ago.
Gardner told SAFC TV: "It's unbelievable, to be honest. As soon as I found out Sunderland were interested, it was a no-brainer.
"Obviously, I have heard so much about Steve Bruce and his backroom staff and how good a chairman Niall Quinn is.
"It's such a massive club and their ambitions for this season meet my ambitions, and it was too good to turn down."
His arrival at the Stadium of Light comes hot on the heels of the capture of teenage striker Connor Wickham on Wednesday while South Korea international Ji Dong-won completed his move to Wearside earlier on Thursday.
Gardner's move ensures he remains in the Premier League following Birmingham's relegation last season.
That was despite Gardner enjoying the best season of his career, finishing as the club's top scorer with 10 goals, which included the clincher in the Blues' 2-0 home win over Sunderland in April.
Black Cats boss Steve Bruce has also agreed deals for Keiren Westwood and Gardner's ex-Birmingham team-mate, Sebastian Larsson, this summer, and is keen on Manchester United trio Wes Brown, Darron Gibson and John O'Shea.
And Gardner is setting his sights high after hearing Bruce's recruitment plans, as he said: "It means that the club wants to go places.
"Obviously, we want to finish as high up the table as we can - we want to be in Europe next year and it's a great task to go and chase.
"It's a good goal for us and we can go and do it, and I am sure we will."